Method for the production of dense compacted silicon carbid.



UNITED s'r r s PATENT OFFICE.

FRANK J. TONE,

OF NIAGARA FALLS, NEW YORK, ASSIGNOR TO THE CARBORUNDUM COMPANY, OF NIAGARA FALLS, NEW YORK, A CORPORATION OF PENNSYLVANIA.

992,698: No Drawing.

To all whom it may concern;

Be it known that I, FRANK J. TONE, of

Niagara Falls, in the county of Niagara and State of New York, have invented a new and useful Method for the Production of Dense Compacted Silicon Carbid, .of which poses and other uses in the arts.

. 285,462, filed November 1, 1905, 1 have dethe penetration of the In my pending applicatioi; Serial No.

scribed and claimed a method in which ,shaped pieces of carbon re heated in proximity to a silicon-containing ubstance to a temperature sufiicient to cause the silicon to combine with the carbon in situ, thus producing similarly shaped pieces of dense silicon carbid. I have discovered that if the carbon in the piece to be treated is replaced by a mixture of silicon carbid and carbon, conversion into silicon carbid is increased, and I am furthermore able to obtain difi'erent values in porosity and resistance which make the product of Wider utility. I

To carry out this invention, I take a mixture of silicon carbid and carbonaceous material, both of which materials are prefer ably ground to a fine state of division, and this mixture is then molded 'or otherwise formed into any desired shape, preferably by mixing with some bindin material, such as tar, glue or silicate of so a.. The article is then preferably baked at a temperature sulficient to remove moisture and other volatile materials. The article is then placed in an electric furnace of the type ordinarily used in the production of carborundum and is embedded in a mixture of carbon and silica,- or silicon carbid and silica. The furnace is brought up to the temperature of the formation of carborundum, atwhich temperature vapors of sil ca and 81110011 are formed and.

Specification of Letters Patent.

changing the subjected, and

, silicon carbid and forming METHOD FOR THE PRODUCTION OF DENSE COMPACTED SILICON CAR-BID.

Patented May 16, 1911.

AplialicationfiledJuly 28 1910. Serial No. 574,357.

vapors of silica and silicon. When these vapors come in contact with the carbonaceous material'contained in the molded ar-v ticles, they react with the carbon and change it into silicon carbid. The binder used for forming the molded article is decomposed or volatilized and the resultant product consists of silicon carbidbonded with silicon carbid in a dense compacted form,

I may vary the nature of my product by temperature and the gaseous which the molded articles are in this way obtain products varying in the depth to" which the above mentioned process has taken place, and in this way obtain a product in which the inner part consists of silicon carbid and carbonaceous matter, and the outer part conatmosphere to sists of silicon carbid alone. I may also vary silicon carbid and carused to form the product. crystalline or amorphous coke, charcoal and other formsofcarbonaceous material. I may also vary the sizeof the particles of silicon carbid and carbonaceous material used in forming the molded articles and in this way produce articles of very different physical properties. By changing all these conditions, I am able to vary to' a very large extent the physical condition of toughness, porosity, electrical and specific resistance, etc. Articles formed in this manner are very valuable for refractory purposes since they are composed of silicon carbid alone.

the nature-of the bonaceous material I may take either -Iclaim:

1. The method of making shaped pieces of dense silicon 'carbi d, which consists in similarly shaped pieces from a mixture heating said pieces in proximity to a siliconcontaining substance to a temperature sufiicient to causethe silicon to combine with "the carbon in situ, and less than that required to destroy' h resulting compound, substantially as described."

2. The method. of making shaped pieces of silicon carbid, which consists in forming similarly shaped pieces from a mixture of siliconcarbid and carbon, heating saidpieces in proximity to the vapors of a silicon-com taming substance, causing the combination of the silicon with the carbon in situ, the

of silicon carbid and carbon and temperature being suflicient to cause the f silicon and carbon to combine but insufficient to destroy the resulting compound, substantially as described.

3. The method of making dense silicon carbid, which consists in forming a shape from a mixture of silicon carbid and carbon, and heating said article-in an atmosphere containing silica and silicon vapors, substantially as described.

4:. The method of making dense silicon carbid, Which consists in forming a body from a mixture of silicon carbid and carbon, with a suitable binder, baking the body to remove moisture and other Volatile substances, and embedding the article in a mixture containing silicon carbid and silica, and heating it to the temperature offormation of carborundum, substantially as described.

In testimony whereof, I have hereunto set my hand.

FRANK J. TONE.

W. A. DWYER. 

